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Action, Reaction

The best definition of the “action-reaction” syndrome was provided by Secretary of Defense Robert McNamara during a deeply conflicted speech before United Press International editors and publishers on September 18, 1967. McNamara used this occasion to rail against the nuclear arms race while endorsing a limited ballistic missile defense, ostensibly against China. [Aspiring wonks: to understand why McNamara would deliver a speech undermining his recommended course of action, check out Mort Halperin’s essay, “The Decision to Deploy the ABM: Bureaucratic and Domestic Politics in the Johnson Administration” in the October 1972 issue of World Politics.]

Here are the key passages:

There is a kind of mad momentum intrinsic to the development of all new nuclear weaponry. If a weapon system works – and works well – there is strong pressure from many directions to procure and deploy the weapon out of all proportion to the prudent level required…

What is essential to understand here is that the Soviet Union and the United States mutually influence one another’s strategic plans.

Whatever be their intentions, whatever be our intentions, actions – or even realistically potential actions – on either side relating to the build-up of nuclear forces, be they either offensive or defensive weapons, necessarily trigger reactions on the other side.

It is precisely this action-reaction phenomenon that fuels an arms race.

McNamara didn’t hold these views when he began his long stint at the Pentagon. Here’s a partial transcript of a private conversation with President John F. Kennedy on December 5, 1962:

McNamara: I think that there are many uncertainties in all of these estimates [of nuclear requirements]. And I would say that my recommendation to you on our strategic forces is to take that requirement and double it and buy it. Because I don’t believe we can, under any circumstances, run the risk of having too few here. So I, in my own mind, I just say, ‘Well, we ought to buy twice what any reasonable person would say is required for strategic forces.’ I think that’s money well spent.

Kennedy: Will it deter?

McNamara: It’s both – it’s principally to deter. And it’s also to give ourselves the confidence that we have that deterrent power…

McNamara became worn down by many cares, including his inability to dampen the Air Force’s, Navy’s and Army’s postulated requirements for nuclear weapons. Arms controllers shared his concerns about the action-reaction syndrome, which lent impetus to campaigns against MIRVs and ballistic missile defense deployments. As MIT’s George Rathjens, who served on defense science panels, wrote in Scientific American in 1969, “Reduction in uncertainty about adversarial intentions and capabilities is a sine qua non to curtailing the arms race.” Rathjens wanted to “somehow break… the action-reaction chains that seem to drive the arms race.” After retiring from active service, some prominent military officers joined this chorus. In 1974, former Chairman of the Joint Chiefs of Staff Maxwell D. Taylor wrote in Foreign Affairs, “Any increase in any kind of strategic weapon stimulates the Soviets to emulation and fuels the arms race.”

No-one stumped harder against the action-reaction syndrome than Paul Warnke, who would become President Jimmy Carter’s Director of the Arms Control and Disarmament Agency and SALT II negotiator. Warnke wrote that,

“The risk is … that we spend too much and build too much and end up with not greater but less true national security. The acquisition of unnecessary strategic systems to gain bargaining strength in negotiations with the Soviet Union will mean only a comparable response from the other side and a conversion of the arms limitation talks into a spur to the arms race rather than a medium for reciprocal restraint.”

Deterrence strategists were greatly alarmed by Warnke’s dual appointments and chafed at McNamara’s formulation. Albert Wohlstetter thundered that the action-reaction syndrome was a “portentous tautology” in a 1974 Foreign Policy essay. Warnke’s rebuttal didn’t help his confirmation when Foreign Policy’s editors, borrowing his phraseology, titled the essay “Apes on a Treadmill.” Harold Brown, President Carter’s Secretary of Defense and a supporter of strategic arms control, held a sadder and wiser view: “When we build up, the Soviets build up; when we slow down, the Soviets build up.”

The action-reaction syndrome was a staple of the superpower nuclear competition. It was especially pronounced when MIRV and BMD technologies were maturing in the late 1960s and early 1970s, and later when new types of intermediate-range missiles made their appearance in the late 1970s and early 1980s. Asymmetries in force structure and different time lines for the roll out of new capabilities ensured compensatory steps.

Washington and Moscow weren’t always in lockstep, but they always competed. Even caustic critics like Wohlstetter acknowledged this. His complaint, widely shared by arms control skeptics, was that the United States wasn’t competing strenuously enough.

Michael Krepon

Writing on ACW 2009–2022

Michael Krepon is the co-founder of the Stimson Center and the author of Winning and Losing the Nuclear Peace: The Rise, Demise, and Revival of Arms Control. He was given a lifetime achievement award for non-governmental work to reduce nuclear dangers by the Carnegie Endowment for International Peace in 2015. He has worked in the executive and legislative branches of the U.S. Government, and taught as a professor of practice at the University of Virginia.

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